Pre-injection of the fuel is known in internal combustion engines and serves to reduce combustion noise. Pre-injection has hitherto been achieved by the application of various means, e.g. fitting additional control spool valves in the injection pipe as flow dividers, or using additional injection pumps and nozzles for pre-injection only. However, the means known hitherto still do not resolve the problem satisfactorily because these means need a considerable amount of space on the engine, increase the prime cost and/or do not ensure a clear division between pre-injection and the main injection phase. Moreover they do not always permit the whole range of loads and speeds to be regulated as desired. It is an object of the present invention to avoid these drawbacks in the known types of construction and at the same time to shape the pump elements used for the main injection phase so as to enable them to also be used for pre-injection, ensuring the desired division between pre-injection and main injection and extensive governing over the entire range of engine loads and speeds.